N. diplotylia N. expallescens N. hawaiensis N. peninsulae N. sorediata Nadvornikia is a genus of lichen-forming fungi in the family Graphidaceae.

The genus was circumscribed in 1984 by lichenologist Leif Tibell, with N. hawaiensis assigned as the type species.

Nadvornikia is a replacement name for Stephanophoron, which was published illegitimately by Czech lichenologist Josef Nádvorník in 1942 (because the fungal genus Stephanophorus already occupied that name).

The cortex, which is absent or loosely arranged, features an irregular photobiont layer with Trentepohlia green algal cells and calcium oxalate crystals.

Vegetative propagules in Nadvornikia lichens may be absent or present as soredia.